The articles and essays in this blog range from the short to the long. Many of the posts are also introductory (i.e., educational) in nature; though, even when introductory, they still include additional commentary. Older material (dating back mainly to 2005) is being added to this blog over time.

Thursday, 6 August 2015

Against David Lewis's Intrinsic Properties

At first sight, the word 'intrinsic' appears to be a virtual - or even literal - synonym of the word 'essential'. Indeed it's tempting to use the latter - rather than former - word. However, as often happens in philosophy, there are indeed slight differences between the two ontological categories. Or, at the very least, there are different definitions of the words 'intrinsic property' and 'essential property'. Nonetheless, it can still be said that the two categories are very closely related. Or, to put that another way, this “sign-substitution” (to use Derrida's term) of 'intrinsic' for 'essential' would never have happened if essentialism and anti-essentialism had never been such important parts of the Western philosophical tradition.In
any case, some metaphysicians tell us that there's a difference
between properties which objects have independently of any external
factors acting upon them (i.e., intrinsic properties) and properties
which are deemed to be the way they regardless of what's external to
them (i.e., essential properties). Despite saying that, can't that
account of intrinsic properties also be applied to essential
properties? Can't we also say that essential properties are those
properties which are independent of any - or all - external factors?

It's
true that this wasn't how essential properties were usually defined
in the tradition. Nonetheless, it actually seems like a good
definition. And if that's the case, then what's happened here isn't
the discovery of another ontological category: it's a new way of
accounting for an old ontological category. That is, when essential
properties are defined in such a way as to emphasise their
independence from all external factors, those properties become
intrinsic
in nature – even though they're exactly the same as essential
properties! Again, the only thing that's changed are our definitions
and/or accounts.

David
Lewis on Intrinsic Properties

This
is David Lewis's definition of intrinsic properties (1982):

“A
thing has its intrinsic properties in virtue of the way that thing
itself, and nothing else, is.”

Could
there ever be such a state as “the way that a thing itself is”
regardless of everything else? That is, regardless of its relations
to other properties/objects/events; its place in time and space; and
so on?

This
position is taken to its most extreme (or perhaps ridiculous) in the
following statement:

Object
a would still have intrinsic property P if after the
world around it disappeared a would still have P.

Can't
we still say that there are intrinsic properties; though they have vital
relations to extrinsic properties? That is, extrinsic proprieties may
determine - to some extent at least - intrinsic properties. However,
it may be countered that because objects are such-and-such-a-way,
then they can only be affected or determined in particular ways
because they have intrinsic properties which are the way they are. That means
that there may be some kind of mutual relation between intrinsic and
extrinsic properties; as well as between extrinsic and intrinsic
properties. Indeed, as I said, there may be no “way” an object is
regardless of its relations to other things or to extrinsic
properties.

David
Lewis also cited “internal structure” as being intrinsic to
objects.
Yet if structure is defined in terms of its relations, then surely it
must also be defined (partly) in terms of extrinsic properties. Thus
Lewis's internal structures would be defined - or even constituted -
by external relations or extrinsic properties. It can now be asked
what would be the point of a Lewisian internal structure if it
weren't primarily a crutch (or framework) for intrinsic properties
which bore
no such relations to external factors.

It
can now be said that internal structures determine relations and
therefore also determine extrinsic properties. Then again, it can
equally be said that external relations (or extrinsic properties)
determine internal structures (or intrinsic properties). Here again
the boundaries between what's intrinsic and what's extrinsic seems to
blur somewhat.

Different Surroundings

David
Lewis also wrote something about an intrinsic property which isn't
entirely helpful until one's entirely sure what such a property
actually is. He writes:

“
… If
something has an intrinsic property, then so does any perfect
duplicate of that thing; whereas duplicates situated in different
surroundings will differ in their extrinsic properties.” (1982)

The
problem with that definition (or stipulation!) is that if a “thing”
is in “different surroundings” it may also have different
intrinsic properties to the ones it had in its previous
surrounding/s. Or to put that more clearly:

i)
Object a has set of intrinsic properties I in
surrounding S.

ii)
Object a has set on intrinsic properties I2 in
surrounding S2.

To
put that in more basic words, object a may change its
intrinsic properties (not only its extrinsic properties) in different
places. And that, surely, will depend on its relations to other
objects; as well its relations to events or properties.

Surely
the conclusion to this is that it's very hard to distinguish
intrinsic from extrinsic properties. Thus why not give up on the
distinction altogether?

In
argument form:

i)
If object a changes its intrinsic properties in “different
surroundings” (Lewis).

ii)
Then a distinction between intrinsic & extrinsic properties will be
difficult to make. iii)
Therefore get rid of the distinction between intrinsic & extrinsic
properties entirely.

There's
an additional way of looking at conclusion iii) above. Thus:

i)
If the intrinsic/extrinsic distinction fails for objects.

ii)
And the having of intrinsic properties is said to be fundamental for
the discernibility, individuation, etc. of objects. iii)
Then the ontological reality of objects itself may be questioned.

Shape as an Intrinsic Property

Lewis believed that the shapes of (some?) objects are intrinsic to such objects. However, don't the shapes of many – or all – objects change through time? Indeed one shape-changer is said to be the curvature of space itself. More correctly, objects (at least to some minute degree in many cases ) help curve space and space itself helps shape objects. Thus shape will depend on the curvature of space. What's more, the curvature of space may be continuously working as a shape-changer.

Unless,
that is, object a's shape at time t is intrinsic and object
a's (slightly different) shape at t2 is then
also intrinsic to it. Though if a's shape were always
changing, its intrinsic properties would also be changing. That's
because it would have two intrinsic shapes at two different times.
And that seems to go against the notion of intrinsicality.

Having
just put the case for space's impact on the shape of objects, I'm not
entirely convinced by it.

My
first thought was that the curvature of space could never have an
impact on the shape of, as J.L. Austin put it, “medium-sized
dry goods” (or macro-objects). The curvature of space does
indeed have an impact on how such objects travel through space (as
well as vice versa); though even here the impact is minute. (Massive
objects, such as the earth, are a different matter.)

So
what about particles and other micro-phenomena? I believed that the
curvature of space didn't have any impact at the quantum
level;
though I may be wrong about that. After all, such curvature only
occurs at the extremely-large scale. And, as I've just said, it won't
even have an impact on everyday objects such as persons or trees
either.

Intrinsic Relations

An
interesting addition to the theory of intrinsic/external properties
would be the category of intrinsic
relations.

Intrinsic
relations are said to determine or even constitute objects. In other
words, they're fundamental to the objects which have them.

That's
primarily the case because an object's intrinsic relations to other
objects (or set/s of properties) are actually constitutive of what
that object is. In other cases, an object's relations aren't
constitutive – or part - of that object's fundamental nature.

For
example, the properties being
two mile away from
can be deemed to be an intrinsic relation. Similarly, the property of
being
the same species as
can also be seen that way.

Clearly,
if object a
is two miles away from object b,
then b
must also be two miles away from a.
Thus, in this case, the property two
miles away from
is symmetrical in regards to a
and b.

Similarly
with the property being
the same species as.
If object a
is
the same species as object b,
then b
must be the same species as a.

However,
how can relational properties be deemed to be intrinsic? It's
certainly counterintuitive to say that being
two miles away from
could be an intrinsic property or, indeed, to be any kind of property
of an object... Unless, of course, that relation remains constant
through time.

What
about the property
being the same species as?
Surely in the case of object a
we can say that its being a member of species S
is fundamental or intrinsic. However, why should we say the same
about the property being
the same species as?
That seems to be a needless addition to the ontology of properties.

It
can certainly be said that a pair of particles can be said to display
or partake of intrinsic relations.

For
example, say that electron
a
and positron b
stand in relation R
to one another. (Many other complex aspects of quantum entanglement
may make the following statements problematic; if not downright
false.)

Thus:

R
is an intrinsic relation iff a (always) stands in R to
b and b (always) stands in R to a.

That
relation will also determine the nature of both a and b.
In fact it can be said that the intrinsic relation is actually
constitutive of the natures of both a and b.

Electron
a and positron b (or any pair of objects), on the other
hand, may be related to all sorts of other objects, properties or
events which don't help constitute their fundamental nature or
intrinsic nature/properties.

In
ontic structural realism, this category of intrinsic relations is
certainly taken to be true about subatomic particles. Yet ironically
this leads (some?) ontic structural realists to deny that there are
objects at all.

Could
this also be applied to macro-objects such as persons or trees? And
need we follow the ontic structural realists in denying that there
are objects simply because they have fundamental relations to - or
indeed are partly constituted by – other objects, events or
extrinsic properties?

Duplicates?

If
there were a “perfect
duplicate”
of David Cameron, according to Lewis, then that duplicate and Cameron
would share the same intrinsic properties.

Thus
the idea of a perfect duplicate sharing all intrinsic properties is
helpful for possible-worlds theory in which counterparts share such
intrinsic properties. Thus:

If
a and b are of the same kind (or are duplicates), then
they must share all their intrinsic properties (even if they have
different extrinsic properties).

In
a certain sense, it's said that objects and even persons must have
intrinsic properties in order to exist as the objects and persons
they are over time. If there were no intrinsic properties, then an
object or person would only last for a second or even less. Thus
could it really be seen as an object or self/person in the first
place?

However,
if there were a duplicate of Cameron, wouldn't that duplicate also
share all his extrinsic properties? To put that more simply, wouldn't
it share all his properties by virtue of it/him being a duplicate?
This conclusion may simply amount to the inappropriate usage of the
word 'duplicate' on Lewis's part. After all, on Lewis's picture,
counterparts only duplicated the intrinsic/essential properties of the
objects they are counterparts of.

But
wouldn't that be begging the question?

Counterpart
theory is primarily used to distinguish intrinsic from extrinsic
properties. However, in order to have duplicates one must already be
committed to intrinsic properties in order to define what is and what
isn't duplicated. So rather than discovering intrinsic properties
through counterpart/duplicate theory, one actually assumes them.
Moreover, not only is the existence or reality of intrinsic
properties assumed, so is what is and what isn't an intrinsic
property.